Well, I tried it and it worked... sort of.
I guess I didn't realize how long it takes to convert a long DivX movie to MPEG (like 5 or 6 hours for 90 minutes or so). Once it is converted, the quality has been taken down-- and the size of the movie has been reduced to about 320x240. In addition, it plays back kind of choppy on my Mac and in my DVD player.
Thanks for the tip, but it looks like for my use, this is way too much of a pain in the ass to see a movie on my TV. I guess until I can get myself a video card with s-video or composite out, I will have to settle for watching a smooth, good-quality DivX on my Mac.